Review: Zeovit system by


I've long made it clear that I'm a fan of the end results the Zeovit Ultra Low Nutrient can create, says Jeremy Gay, so six months ago I decided to have a go myself, got some ‘blue bottles' and bright orange reactors...

The Zeovit system is a method or formula for keeping delicate SPS corals in reef tanks by providing water that’s very low in nitrate and phosphates. Once you’ve lowered nutrients sufficiently you can add small amounts of supplements to tweak the coloration of the coral tissues themselves— be they green, blue, pink, purple or yellow.

If unfamiliar with the method, check out our article called 'A reef tank full of colour'.

If you search online for 'Zeovit reef tank' you’ll see lots of Acropora-heavy reef tanks, all of them very colourful, even pastel coloured.

The combination of very low nutrients and tiny amounts of additives have stripped away the brown coloration from the tissues and heightened the coral colours underneath. For some reef keepers those aquascapes represent the ultimate experience.

Not all like it though and some feel the corals look bleached and the effects are un-natural, even resembling a dark art.

I prefer to be open-minded and after following the results for a good seven years now I’ve seen the same ‘bleached’ corals grow, flourish and get fragged. is a forum dedicated to the method and it has grown to some 10,000 members, so I don’t think it’s the fad or flop that some rivals had predicted.

Furthermore, with Red Sea’s new Reef Care Programme selling fast it’s got more than a hint of the nutrient reduction and colour-enhancing technologies that Korallenzucht’s Thomas Pohl came up with some ten years ago, so the principles are now widely used throughout the marine hobby.

Getting started

The Zeovit method can be gradually introduced to existing reef tanks, although many, including me, started from scratch with a newly set-up tank — the reason being that a long-term reef tank may have nutrients pooled in its rocks, sand and decoration which, via gradual leaching over  the passage of time, could skew the desired results.

In addition, and this is fundamental to the methodology, the makers state that you shouldn’t use phosphate-removal resins, algal refugiums or UVs, which many people do run, so I waited for it to coincide with a new tank set-up then started my work from scratch.

If considering Zeovit for a small tank there’s a nano range of supplements, although they don’t make small reactors and the tiny amounts of flow needed through the reactors may make full implementation of the system appear a bit tricky.

Again, you’ll notice online that most Zeovit tanks are large to very large in size.

I started with what Korallenzucht advised —namely its own blend of Zeolites (the ‘zeo’ in the Zeovit brand name), one of its Zeovit reactors, Zeobac, (denitrifying bacteria,) ZeoStart (carbon source to feed the bacteria,) and the company’s own activated carbon. Those components make up the basis of the whole nutrient reduction system.

Put the Zeovit stones in the reactor, place the carbon loose in a bag and dose daily the bacteria and their food to get started.

Korallenzucht also recommends regular use of a product called Sponge Power (food for sponges in your live rock) and ZeoFood (food for corals and bacteria.)

Also critical to the method are good quality live rock, ideally freshly cured, a good protein skimmer, strong water flow and adequate lighting for the corals.

Korallenzucht produces its own range of T5 bulbs to complement the range and a salt. Natural seawater parameters are sought, which was a new one on me as I’ve always been in the elevated levels of KH, calcium and magnesium camp before trying this method.

The KZ website includes a guide to getting the system part- matured and containing some SPS corals in as little as 14 days.

This is the path the supplier recommended and the one I tested for this review. Follow it to the letter as I did and, unless you do something very wrong, those elusive acropora will easily be in reach.

You’ll see a bit of algae come then go, your coral colours lighten, and then, depending on what you add next, change very much for the better. It will all need daily attention, but overall I’m impressed with the outcome.


If you keep marines, have some spare cash and like a challenge, the Zeovit system can produce some stunning results. I liked it before reviewing it and now I’ve tried it I’m continuing to use it, and trying out a few different blue bottles from the substantial range to see how they affect my corals too.

Of all the low nutrient methods available, this is probably the most expensive because of that Zeovit reactor you need to buy, but it probably has the most devotees. The blue bottles aren’t cheap either, although they are very concentrate and I dosed just four tiny drops per day on a 400 l/88 gal system.

Zeovit will only offer good results if you provide otherwise perfect conditions like light, temperature, salinity, even parameters like potassium, and won’t be forgiving if you neglect the dosing and maintenance. Most people who go wrong with it stray off the path early on and the problem can always be traced back to that stage. However, some reefers seem to do everything right and still can’t nail it.

Although not for beginners, the Zeovit method can offer truly outstanding results. Zeovit forum members are the nicest bunch of people I’ve met online and if you follow their advice and don’t mind being a bit OCD with your tank’s testing and dosing, you’ll be a Zeohead in no time — and with a world-class reef tank.

Price: From £250-500 to get started, depending on tank size and brand of media reactor. KZ branded reactors and extra products may add to that total. Contact ITC Aquatics to find a nearby stockist.

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